This invention relates to a device for removing moisture from lubricating and other types of oils circulated and supplied to machinery.
Trace amounts of moisture are generally present in oils such as lubricating oil. When the amount of moisture present is less than the saturation solubility, the water and oil remain coalescent and united. Under such conditions, the various properties required of an oil in oil circulation equipment, such as viscosity, fluidity, compressibility, lubricity, and rust-inhibiting effects, may be properly maintained. However, when moisture enters the oil from the atmosphere, machinery, or other sources, the water content of the oil rises above the saturation solubility. The excess moisture becomes liberated from the oil, and adversely affects certain properties of the oil such as its rust-inhibiting effects and lubricity. When oil containing free water is circulated through machinery, this accelerates rusting and the reduced lubricity of the oil aggravates the friction and wear of sliding and rubbing parts. The resulting decrease in oil viscosity also has a number of adverse effects, such as a reduced sealing action.
Various devices have been conceived for eliminating such problems. One such device is an oil-water separator that uses the difference in the specific gravities of oil and water to precipitate water liberated from the oil when the water content rises above the saturation solubility of the oil; the precipitated water is trapped and collected in a moisture precipitation tank. Another device separates and removes moisture from oil by causing the water to adhere to a cloth belt. All these devices remove water liberated from oil, and so do not function until the excess moisture dissociates from the oil. This means that, following liberation from the oil, the free water stands a very good chance of circulating through the machinery together with the oil until it is removed from the system by one of these devices. It is common especially in precision machinery for very small quantities of moisture to enter the oil gradually over long periods of time. When this happens, the oil clouds, following which the water and oil begin to dissociate. With conventional devices of the type just described, a considerable period of time elapses from the time at which the water and oil begin to dissociate up to the removal of the free water. During this period, there is a constant danger of the moisture circulating within the machinery, causing equipment deterioration and damage.